<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
张三
{{ r2 }}
{{ data1.name }}
{# 文字 #}
{% if data1.age < 18 %}
    {{ data1.name }}
    <ul>
        <li>1</li>
    </ul>
{% elif data1.age==18 %}
    do something
{% else %}
    none
{% endif %}
{% for key,val in data1.items() %}
    {{ key }}{{ val }}
{% endfor %}


</body>
</html>